Brian Belski thinks this could be the last great bull market of his career.

"We've been very clear over the past several years that we believe that we have entered a 15- to 20-year equity bull market, [a] secular bull market," the chief investment strategist at BMO Capital Markets said Monday on CNBC's "Squawk on the Street."

"I'm getting out at the end of this one."

Investors could still see a sideways market next year, he added, especially as the markets shift toward fundamentals and away from the Fed's easy money policies, but that would be "healthy" for a long-term bull market.

Belski added that the market could weaken in the latter half of 2014 after the S&P 500 breaks 2,000, but that it should post gains at year's end.

"I think the biggest surprise in 2014 is that the U.S. stock market continues to outperform, especially considering that many of our clients on the institutional side have started to bottom fish Europe and [emerging markets], and we think it's too early," Belski said.

Challenges to a bull market include strong growth causing the Fed to act more aggressively than Wall Street wants and unforeseen threats to stability from global hot-spots, Belski said.

Strong plays next year include a diversity of industrials, conglomerates and machinery to take advantage of ongoing recovery, Beksli said. He said the next phase of the bull market will be earnings and sales growth driven by capital expenditure and financial services.

—By CNBC's Jeff Morganteen. Follow him on Twitter at @jmorganteen and get the latest stories from "Squawk on the Street."